The lotus was half a foot above the water, and suddenly the south wind blew it down. Lotus is just submerged in the water. In autumn, the farmer found that the fallen flowers were two feet away from t

The lotus was half a foot above the water, and suddenly the south wind blew it down. Lotus is just submerged in the water. In autumn, the farmer found that the fallen flowers were two feet away from the roots. How can I ask? Knowledge point: right triangle

Idea: First of all, we should extract useful information from this little poem.

The first sentence tells us that when there is no wind, the lotus is half a foot above the water, that is, the position of the lotus is 0.5 from the water;

The second sentence tells us that the wind blows the lotus obliquely, and the lotus is just submerged under the water, that is, the lotus is located on the water;

The third sentence tells us that the lotus was discovered by fishermen after autumn, that is to say, the lotus must have fallen by this time;

The fourth sentence tells us that the place where the flower falls is two feet from the root, that is, the place where the flower falls is two feet from the root. Let's find out the depth of the water.

As shown in the figure, OA is the position of the lotus when there is no wind, point A is the position of the lotus at this time, OB is the position of the lotus after the wind blows, point B is the position of the lotus at this time, and BC is the water depth. According to the above information, OC is the distance from the fallen flower to the root, OC=2, OB=OA=BC+0.5, and the length of BC is found.

In Rt△OBC, OB2=OC2+BC2 can be obtained according to Pythagorean theorem. Just substitute it into the calculation.